Although natural gas meters generally operate in a reliable and trouble free manner for a number of years, if service or repair is not sooner necessitated by damage to the meter or concerns over the accuracy of the meter, all must eventually be taken out of service for maintenance, calibration or replacement. Because of safety and accuracy concerns, regulatory agencies who have jurisdiction over gas utility companies, typically require change out of gas meters within a prescribed time period. Typical mandated change out periods range from 10 to 15 years.
One of the principal concerns that gas utility company service personnel must address in changing out or servicing a meter is the necessity to accomplish the change out or service without interrupting the supply of gas to the residential or commercial user. If the supply of gas to the user is interrupted, even momentarily, pilot lights will be extinguished. At the very least, this then requires the service technician to enter the home or business and re-light the pilot lights for each of the user's appliances. Further, utility company policies and good safety practice usually require that the service technician check the user's appliances over for additional safety concerns, prior to re-lighting the pilots. If, as is often the case with residential customers and even commercial customers during non-business hours, a service technician must return to the customer's address on one or more occasions to obtain access to the customer's premises and appliances. Further, additional health and safety concerns arise in cases where property owners cannot be found for an extended period of time following a disruption of service.
Because of the foregoing concerns, gas utility companies have generally adopted the policy that meter change out or service, for all residential users and most commercial users, must be accomplished without a disruption of service. Accordingly, a number of methods and apparatuses have been developed over the years to attempt to deal with this concern. However, all of the previously disclosed methods and apparatuses have substantial limitations.
Most of the attempts to deal with this concern require special and costly piping, fittings, valves, and other apparatuses to be installed at each meter installation. Examples of this type of approach are shown in U.S. Pat. No. to Douglas 2,579,656, Mueller U.S. Pat. No. 3,187,570, Anderson U.S. Pat. No. 3,245,257, Mueller U.S. Pat. No. 3,296,861, Gilpin U.S. Pat. No. 3,444,724, England U.S. Pat. No. 5,042,526, Russell U.S. Pat. No. 5,178,188, Winnie U.S. Pat. No. 5,437,300, and Winnie U.S. Pat. No. 5,482,073. These approaches also require costly and time consuming re-plumbing of existing installations in order to retrofit existing installations with the specialized piping, fittings, valves, and other apparatuses. Another problem with a number of these attempts is that they involve the use of special apparatuses in the gas service line itself that restrict the flow of gas and involve potential for clogging, plugging, or malfunction prior to or at the time that a meter bypass is needed. For example, this problem is evident in the inventions described in U.S. Pat. No. to Russell 5,178,188, Winnie U.S. Pat. No. 5,437,300 and Winnie U.S. Pat. No. 5,482,073.
Several of the attempts to deal with this concern also substantially increase the probability of customer bypass of the meter, allowing a theft of gas by the customer. For example, this is a problem with the inventions disclosed in U.S. Pat. No. to Douglas 2,579,656, Mueller U.S. Pat. No. 3,187,570, Mueller U.S. Pat. No. 3,296,861, and Gilpin U.S. Pat. No. 3,444,724.
Also, a number of the inventions disclosed in the prior art do not provide an effective way of purging air from the piping and apparatuses or otherwise eliminating the possibility of air being introduced into the customer service line at the time of the meter bypass. Even minute amounts of air mixed with natural gas can result in a instantaneous lack of fuel or a minute explosion event occurring in an appliance pilot gas orifice, thereby extinguishing the pilot. The inventions disclosed in U.S. Pat. No. to Anderson 3,245,257, England U.S. Pat. No. 5,042,526, Winnie U.S. Pat. No. 5,437,300, and Winnie U.S. Pat. No. 5,482,073 involve the significant risk of this type of problem. It is, therefore, crucial that a bypass method or apparatus provide for the elimination of air which would ultimately find its way to the customer service line.
The most widely used method and apparatus for the change out of gas meters in the natural gas utility industry is that disclosed in U.S. Pat. No. 3,148,690 to Petersen. This method and apparatus has an advantage over the other alternatives disclosed in the prior art as identified above. This device is used with a standard meter installation with no special piping, fittings, or valves being required.
The standard meter installation preferred by most gas utility companies include a shut-off valve and a pressure regulating valve on the supply side of the meter and a standard tee on the customer side of the meter. The shut-off valve is used to turn the gas on and off for customer service.
The pressure regulating valve reduces the pressure from the higher main line pressure, which will typically ranges between 40 psi and 80 psi, to the lower pressure utilized in homes and business, which historically has ranged from the 4 oz. of pressure used for most homes to a maximum of 2 psi for some residential and commercial users. There is a growing interest in utilizing higher pressure for both homes and businesses. The use of 2 psi or higher pressures in homes allows the use of easily installed coils of smaller diameter tubing for gas systems rather than the larger 1/2 inch to 3/4 inch iron pipe historically used, which must be installed by traditional plumbing methods. Likewise, commercial installations are now utilizing pressures of 10 psi or higher, in order to reduce the size and cost of the piping.
The standard tee on the customer size of the meter is the only fitting installed in a typical installation for use in bypassing the meter. As indicated above, the gas companies prefer this typical installation for cost and security reasons. Therefore, for a bypass apparatus to meet the needs of the gas utility companies, it must connect to this standard tee only.
As indicated above, presently the most widely used apparatus and method for gas meter change out and service is that disclosed in U.S. Pat. No. 3,148,690 to Petersen, which interfaces with the standard tee on the customer side of a meter. A principal problem with the Petersen device is that it is not adaptable to higher pressure installations. Because it incorporates a gas bladder which inflates as the alternate gas source is used to energize the customer service but must be thin and pliable enough to be gripped upon the tee plug, it is limited to the lower 4 oz applications. This device is impractical even for the 1 psi or 2 psi range now being utilized for many residential users. It is entirely unworkable for the 10 psi service pressures being utilized for some commercial applications. It is also obvious, from an examination of the device itself, that it is a cumbersome and slow method which unexpectedly meets with the continuing disfavor of service personnel. Gripping the plug, which has been pre-loosened with a wrench, by collapsing the bladder upon the plug by hand in the area of the tee, is awkward at the very least. The process of turning the plug by hand is then also slow and awkward, as the bladder must be collapsed and gripped upon the plug, the plug turned a partial revolution, and the bladder released. This process is repeated over and over until the plug is removed and falls to the bottom of the inflated bladder. Thereafter, the entire air contaminated gas contents of the inflated bladder must be bled from the bladder before a temporary plug can be advanced by hand into the tee, shutting off the gas supply from the meter and limiting the customer service to the alternate gas supply. After the change out or service work is completed, to reinstall the plug, the loose plug must be gripped by collapsing the bladder around the plug and physically moving the plug back into position to be advanced into the tee in the same manner that it was removed.
It is easy to see why service personnel would be desirous of an alternative to the method and apparatus disclosed in the Petersen patent. However, that apparatus and method is the industry standard and has been used by most utility companies for many years.
Therefore, a method and apparatus is needed which would provide for the more expeditious bypassing of a gas meter without interruption of service to the customer, which is compatible with standard meter installations, and which can be used for the full range of customer service pressures from 4 oz. up to 10 psi or more. The present invention provides a single method and apparatus for the full range of service pressures. It is fully compatible with standard meter installations as it attaches to the standard service tee. It requires no retrofit for existing meter installations.
One objective of the present invention is to provide a method and apparatus for gas meter bypass and change out which is compatible with standard gas meter installations and requires no additional fittings, piping, valves, or other apparatuses for gas meter bypass and change out.
A further objective of this present invention is to provide a method and apparatus for gas meter bypass and change out which will increase the ease and speed by which gas meter bypass and change out can be affected.
A still further objective of the present invention is to provide a method and apparatus for gas meter bypass and change out that will work efficiently and effectively for the full range of service of pressures encountered for residential and commercial users.
A still further objective of the present invention is provide a method and apparatus for gas meter bypass and change out which provides for the expeditious and reliable expulsion of air from the bypass apparatus, thereby eliminating the potential for air being mixed with the gas which is transmitted to the customer's appliances.
A still further objective of the present invention is to provide a method and apparatus for gas meter bypass and change out which minimizes the potential for customer bypass of meters and the resultant gas theft.
A still further objective of the present invention is to provide a method and apparatus for gas meter bypass and change out which is durable and reliable for continuous and high repetition use.
A still further objective of the present invention is to provide a method and apparatus for gas meter bypass and change out which would be readily accepted by service personnel and increase their productivity.